The present invention relates to cryptographic systems. In particular, the present invention relates to a system for formulating cryptographic keys used to encrypt plaintext messages and decrypt ciphertext communications.
In the modern world, communications are passed between parties in a variety of different ways utilizing many different communications media. Electronic communication is becoming increasingly popular as an efficient manner of transferring information, and electronic mail in particular is proliferating due to the immediacy of the medium.
Unfortunately, drawbacks accompany the benefits provided by electronic communication, particularly in the area of privacy. Electronic communications may be intercepted by unintended recipients. Wireless transmissions, such as voice communication by cellular telephone, and electronic mail are especially susceptible to such interception.
The problem of electronic communication privacy has been addressed, and solutions to the problem have been put in place. One form of solution uses cryptography to provide privacy for electronic communication. Cryptography involves the encrypting or encoding of a transmitted or stored message, followed by the decryption or decoding of a received or retrieved message. The message usually takes the form of a digital signal, or a digitized analog signal. If the communication is intercepted during transmission or is extracted from storage by an unauthorized entity, the message is worthless to the interloper, who does not possess the means to decrypt the encrypted message.
In a system utilizing cryptography, the encrypting side of the communication incorporates an encoding device or encrypting engine. The encoding device accepts the plaintext (unencrypted) message and a cryptographic key, and encrypts the plaintext message with the key according to an encrypt relation that is predetermined for the plaintext communication and the key. That is, the message is manipulated with the key in a predetermined manner set forth by the text/key relation to produce a ciphertext (encrypted) message.
Likewise, the decrypting side of the communication incorporates a decoding device or decrypting engine. The decoding device accepts the ciphertext message and a cryptographic key, and decrypts the ciphertext message with the key according to a decrypt relation that is predetermined for the ciphertext message and the key. That is, the message is manipulated with the key in a predetermined manner set forth by the text/key relation to produce a new plaintext message that corresponds with the original plaintext message.
The manner in which the key and the relation are applied in the communication process, and the manner in which keys are managed, define a cryptographic scheme. There are many conventional cryptographic schemes in use today. For example, probably the most popular of these is a public-key cryptographic scheme. According to a scheme of this type, the keys used are actually combinations of a public key component that is available to anyone or to a large group of entities, and a private key component that is specific to the particular communication.
An important consideration in determining whether a particular cryptographic scheme is adequate for the application is the degree of difficulty necessary to defeat the cryptography, that is, the amount of effort required for an unauthorized person to decrypt the encrypted message. One way to improve the security of the cryptographic scheme is to minimize the likelihood that a valid key can be stolen, calculated, or discovered. The more difficult it is for an unauthorized person to obtain a valid key, the more secure communications will be under a particular scheme.
It is therefore an object of the present invention to provide a process and apparatus for assembling keys which provides added security against compromising a communication by unauthorized entities.
It is a further object of the present invention to provide a process and apparatus for developing key components that cannot be reproduced by unauthorized parties.
These and other objects and advantages are provided by a cryptographic key split combiner, which includes a number of key split generators for generating cryptographic key splits and a key split randomizer for randomizing the cryptographic key splits to produce a cryptographic key. Each of the key split generators generates key splits from seed data.
In one embodiment of the present invention, the key split generators include a random split generator for generating a random key split based on reference data. The random split generator may generate a random sequence based on the reference data, or may generate a pseudorandom sequence based on the reference data. The random key split may further be based on chronological data. The random key split may instead be based on the reference data and on static data, which may be updated. One manner of updating the static data is by modifying a prime number divisor of the static data.
Other key split generators may include, for example, a token split generator for generating a token key split based on label data and/or organization data and/or static data; a console split generator for generating a console key split based on maintenance data, whether previous or current, and/or on static data; and a biometric split generator for generating a biometric key split based on biometric data, which may include biometric data vectors and on biometric combiner data, and/or static data. The label data may be read from a storage medium, and may include user authorization data. The resulting cryptographic key may be, for example, a stream of symbols, at least one symbol block, or a key matrix.
The present invention also includes a process for forming cryptographic keys, which includes generating a plurality of cryptographic key splits from seed data and randomizing the cryptographic key splits to produce a cryptographic key. The cryptographic key splits may include, for example, a random key split based on reference data, a token key split based on label data, a console key split based on maintenance data, and a biometric key split based on biometric data. These key splits may be random sequences or pseudorandom sequences.
Generating the random key split may include generating a key split based on the reference data and on chronological data, or based on the reference data and on static data. Generating the token key split may include generating a key split based on the label data, which may be read from a storage medium and may include authorization data, and on organization data, or based on the label data and on static data. Generating the console key split may include generating a key split based on previous maintenance data and on-current maintenance data, or based on the maintenance data and on static data. Generating the biometric key split may include generating a key split based on biometric data vectors and on biometric combiner data, or based on the biometric data and on static data.
The static data provided for any of the key splits may be updated. Updating the static data may include modifying a prime number divisor of the static data.
The resulting cryptographic key may be a stream of symbols, at least one symbol block, or a key matrix.